Fujimori was ordered to be detained along with 19 other people including her former campaign chief, Jaime Yoshiyama, Bloomberg reported. A court approved Fujimori's detention for 10 days, stating she was a risk to leave the country and could obstruct the prosecutors' investigation.

Prosecutors are investigating several large undeclared financial donations to Fujimori's campaign and whether she received illicit funds from Brazilian construction firm Odebrecht, which has been at the center of the so-called Carwash bribery investigation.

Fujimori denied allegations she received money from Odebrecht, stating the allegations were part of a campaign against her.

Prosecutor José Domingo Pérez said Fujimori had "set up and criminal organisation within her political party" that had "political power and, as a result, a level of influence and interference in legislative and judicial power."

Investigators allege Fujimori's political party laundered undeclared contributions through cocktail party fundraisers, which supporters paid $300 to attend and more than 100 guests' names were falsified to make up for unaccounted funds.

Fujimori's detainment comes after her father, Alberto Fujimori, was jailed Wednesday to complete a 25-year sentence for authorizing death squads after a court ruled to overturn a political pardon.